[Federal Register Volume 88, Number 227 (Tuesday, November 28, 2023)]
[Notices]
[Pages 83081-83098]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-26158]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XD494]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to the City of Oceanside's Harbor 
Fishing Pier and Non-Motorized Vessel Launch Improvement Project in 
Oceanside, California

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Notice; proposed incidental harassment authorization; request 
for comments on proposed authorization and possible renewal.

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SUMMARY: NMFS has received a request from the City of Oceanside for 
authorization to take marine mammals incidental to pile driving 
activities associated with harbor fishing pier and non-motorized vessel 
launch improvement in Oceanside, California. Pursuant to the Marine 
Mammal Protection Act (MMPA), NMFS is requesting comments on its 
proposal to issue an incidental harassment authorization (IHA) to 
incidentally take marine mammals during the specified activities. NMFS 
is also requesting comments on a possible one-time, 1-year renewal that 
could be issued under certain circumstances and if all requirements are 
met, as described in Request for Public Comments at the end of this 
notice. NMFS will consider public comments prior to making any final 
decision on the issuance of the requested MMPA authorization and agency 
responses will be summarized in the final notice of our decision.

DATES: Comments and information must be received no later than December 
28, 2023.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service and should be submitted via email to 
<a href="/cdn-cgi/l/email-protection#db928f8bf5b8b7beadbeb5a8afb2b5be9bb5b4babaf5bcb4ad"><span class="__cf_email__" data-cfemail="e8a1bcb8c68b848d9e8d869b9c81868da886878989c68f879e">[email protected]</span></a>. Electronic copies of the application and 
supporting documents, as well as a list of the references cited in this 
document, may be obtained online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. In case of problems accessing these documents, 
please call the contact listed above.
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. Comments, including all attachments, must 
not exceed a 25-megabyte file size. All comments received are a part of 
the public record and will generally be posted online at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities without change. All 
personal identifying information (e.g., name, address) voluntarily 
submitted by the commenter may be publicly accessible. Do not submit 
confidential business information or otherwise sensitive or protected 
information.

FOR FURTHER INFORMATION CONTACT: Alyssa Clevenstine, Office of 
Protected Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Background

    The MMPA prohibits the ``take'' of marine mammals, with certain 
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. citizens who engage in a 
specified activity (other than commercial fishing) within a specified 
geographical region if certain findings are made and either regulations 
are proposed or, if the taking is limited to harassment, a notice of a 
proposed IHA is provided to the public for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other ``means of effecting the least practicable adverse 
impact'' on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of the species or stocks for 
taking for certain subsistence uses (referred to in shorthand as 
``mitigation''); and requirements pertaining to the mitigation, 
monitoring and reporting of the takings are set forth. The definitions 
of all applicable MMPA statutory terms cited above are included in the 
relevant sections below.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our proposed action (i.e., the issuance of an IHA) 
with respect to potential impacts on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (IHAs with no anticipated serious injury or 
mortality) of the Companion Manual for NAO 216-6A, which do not 
individually or cumulatively have the potential for significant impacts 
on the quality of the human environment and for which we have not 
identified any extraordinary circumstances that would preclude this 
categorical exclusion. Accordingly, NMFS has preliminarily determined 
that the issuance of the proposed IHA qualifies to be categorically 
excluded from further NEPA review.
    We will review all comments submitted in response to this notice 
prior to concluding our NEPA process or making a final decision on the 
IHA request.

Summary of Request

    On May 16, 2023, NMFS received a request from the City of Oceanside 
for an IHA to take marine mammals incidental to construction activities 
associated with fishing pier and non-motorized vessel improvement in 
Oceanside Harbor, Oceanside, CA. Following NMFS' review of the 
application, the City of Oceanside submitted revised versions on July 
18 and October 17, 2023. The application was deemed adequate and 
complete on November 2, 2023. The City of Oceanside's request is for 
take of seven species of marine mammals by Level B harassment only. 
Neither the City of Oceanside nor NMFS expect serious injury or 
mortality to result from this activity and, therefore, an IHA is 
appropriate.

Description of Proposed Activity

Overview

    The City of Oceanside proposes to remove and replace the existing 
public fishing pier and non-motorized vessel launch in Oceanside 
Harbor, Oceanside,

[[Page 83082]]

CA. The purpose of this project is to completely replace the pier and 
launch dock with the goals of making the pier larger, bringing the pier 
to current code standards, and relocating the launch dock to improve 
accessibility. The existing pier is past its design service life and 
has inadequate load-bearing capabilities. The applicant intends to use 
vibratory extraction to remove four 16-inch octagonal concrete support 
piles; vibratory driving to install up to 18 18-inch round plastic-
coated steel piles to within 0.61-1.52 meters (m; 2-5 feet (ft)) of 
required depth; and, potentially, impact driving to complete pile 
installation depending on observed soil resistance. While not expected 
to be required based on site geology, 18 10-inch steel piles may be 
used as temporary guide piles to aid in the installation of the larger 
18-inch structural piles.
    A maximum of 6 non-consecutive days of piling activities is 
proposed to occur during the course of construction (5-6 months) from 
March 2024 through February 2025. The proposed project footprint is 
approximately 0.0081 square kilometers (km\2\; 0.0031 square miles 
(mi\2\)) with water depths ranging from approximately -6 m (-20 ft) 
below mean lower low water (MLLW) and 2.4 m (7.8 ft) above MLLW.

Dates and Duration

    This IHA would be effective from March 1, 2024, until February 28, 
2025. The project is anticipated to occur over a period of 183 days (5-
6 months) from March 1, 2024, through February 28, 2025 (excluding work 
from April 1 through August 31, 2024, to account for the breeding and 
nesting season of the Endangered Species Act (ESA)-listed California 
least tern (Sternula antillarum browni)), and in-water pile activity is 
anticipated to occur for 6 non-consecutive days during that time. The 
City of Oceanside plans to conduct piling activities during daylight 
hours, generally limited to between 45 minutes post-sunrise and 45 
minutes pre-sunset. Pile removal and installation activities may take 
place concurrently, where multiple piles are extracted or installed 
during a day, but not coincidentally. Pile extraction is anticipated to 
take 1 day and pile installation is anticipated to take 5 days.

Specific Geographic Region

    This project would be located at the existing Oceanside Harbor 
Fishing Pier in Oceanside, CA (Figure 1), with depths ranging from 
approximately 6 m below to 2.4 m above MLLW.
BILLING CODE 3510-22-P

[[Page 83083]]

[GRAPHIC] [TIFF OMITTED] TN28NO23.003

BILLING CODE 3510-22-C

Detailed Description of the Specified Activity

    Vibratory extraction of four existing 16-inch octagonal concrete 
support piles would occur in 1 day. Vibratory installation of up to 18 
18-inch round plastic-coated steel pipe piles, with the potential for 
an additional 18 10-inch

[[Page 83084]]

temporary steel guide piles, would occur over 5 days (table 1). If 10-
inch steel guide piles are needed, they will be installed and extracted 
via vibratory hammer within the same timeframe as the permanent piles. 
New 18-inch steel piles will be installed with a vibratory hammer until 
they are within 0.61-1.52 m of the required depth, at which point the 
remaining driving will be done with an impact hammer depending on 
observed sediment resistance. Temporary 10-inch guide piles would only 
be installed to aid in installation of structural 18-inch piles if hard 
sediments are encountered that will deflect pile positioning. All 
activities may occur with or without high-pressure water jetting.

                                                  Table 1--Pile Extraction and Installation Activities
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                                                                                                                         Duration of
                                                                                                         Duration of      vibratory     Estimated  blows
            Pile activity                      Method             Pile size (inch),     Piles per day     activity      activity  per      of impact
                                                                      material                             (days)           pile        driving per pile
                                                                                                                          (minutes)        (strikes)
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Extraction..........................  Vibratory..............  16, concrete..........               4               1              25                N/A
Installation........................  Vibratory..............  18, steel.............               4             * 5              25                N/A
Installation........................  Impact.................  18, steel.............               4             * 5             N/A                300
Installation........................  Vibratory..............  10, steel.............               4             N/A              10                N/A
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Impact pile installation will be used for driving piles 0.61-1.52 m to final depth, depending on observed sediment resistance.
* Vibratory and impact installation of 18-inch steel piles would occur in the same 5 days.

    Other pile removal methods, including removing piles via high-
pressure water jet may also occur, but no take of marine mammals is 
anticipated to occur incidental to this portion of the project and 
these activities will not be discussed further.
    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history of the potentially affected species. NMFS 
fully considered all of this information and we refer the reader to 
these descriptions instead of reprinting the information. Additional 
information regarding population trends and threats may be found in 
NMFS' Stock Assessment Reports (SAR; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and 
more general information about these species (e.g., physical and 
behavioral descriptions) may be found on NMFS' website (https://www.fisheries.noaa.gov/find-species).
    Table 2 lists all species or stocks for which take is expected and 
proposed to be authorized for this activity, and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and ESA and potential biological removal (PBR), where known. 
PBR is defined by the MMPA as the maximum number of animals, not 
including natural mortalities, that may be removed from a marine mammal 
stock while allowing that stock to reach or maintain its optimum 
sustainable population (as described in NMFS' SARs). While no serious 
injury or mortality is anticipated or proposed to be authorized here, 
PBR and annual serious injury and mortality from anthropogenic sources 
are included here as gross indicators of the status of the species or 
stocks and other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS' stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS' U.S. Pacific SARs. All values presented in table 2 are the most 
recent available at the time of publication (including from the final 
2022 SARs) and are available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.

                                       Table 2--Marine Mammal Species Likely Impacted by the Specified Activities
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                                                                                      ESA/MMPA status;   Stock abundance (CV,
            Common name                  Scientific name              Stock           strategic (Y/N)      Nmin, most recent        PBR      Annual M/SI
                                                                                            \2\          abundance survey) \3\                   \4\
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                                                  Odontoceti (toothed whales, dolphins, and porpoises)
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Family Delphinidae:
    Bottlenose dolphin.............  Tursiops truncatus....  California Coastal....  -/-; N             453 (0.06, 346, 2011).          2.7          >=2
    Long-beaked common dolphin.....  Delphinus delphis       California............  -/-; N             83,379 (0.216, 69,636,          668       >=29.7
                                      capensis.                                                          2018).
    Short-beaked common dolphin....  Delphinus delphis       California/Oregon/      -/-; N             1,056,308 (0.21,              8,889       >=30.5
                                      delphis.                Washington.                                888,971, 2018).
    Pacific white-sided dolphin....  Lagenorhynchus          California............  -/-; N             34,999 (0.222, 29,090,          279            7
                                      obliquidens.                                                       2018).
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                                                               Order Carnivora--Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):

[[Page 83085]]

 
    California sea lion............  Zalophus californianus  U.S...................  -/-; N             257,606 (N/A, 233,515,       14,011         >321
                                                                                                         2015).
Family Phocidae (earless seals):
    Harbor seal....................  Phoca vitulina          California............  -/-; N             30,968 (0.157, 27,348,        1,641         42.8
                                      richardii.                                                         2012).
    Northern elephant seal.........  Mirounga                California Breeding...  -/-; N             187,386 (N/A, 85,369,         5,122         13.7
                                      angustirostris.                                                    2013).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Information on the classification of marine mammal species can be found on the web page for The Society for Marine Mammalogy's Committee on Taxonomy
  (https://marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies/; Committee on Taxonomy (2022)).
\2\ ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or
  designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR or
  which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is
  automatically designated under the MMPA as depleted and as a strategic stock.
\3\ NMFS marine mammal stock assessment reports online at: https://www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum
  estimate of stock abundance.
\4\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
  commercial fisheries, vessel strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A
  CV associated with estimated mortality due to commercial fisheries is presented in some cases.

    As indicated above, all seven species in table 2 temporally and 
spatially co-occur with the activity to the degree that take is 
reasonably likely to occur. Based on previous marine mammal monitoring 
events near the mouth of Oceanside Harbor (Merkel and Associates, Inc., 
2022; Merkel and Associates, Inc., 2023), other marine mammals rarely 
occur within Oceanside Harbor and any occurrence in the project area 
would be very rare. While Risso's dolphins (Grampus griseus) and gray 
whales (Eschrichtius robustus) have been sighted outside of the harbor 
and in coastal waters, these species' general spatial occurrence is 
such that take is not expected to occur as they typically occur more 
offshore, and they are not discussed further beyond the explanation 
provided here.

Bottlenose Dolphin

    Bottlenose dolphins (California coastal stock) occur in coastal 
waters within 1 km of shore, primarily between Point Conception, CA, 
and San Quintin, Mexico (Hansen, 1990, Carretta et al., 1998). 
California coastal bottlenose dolphins show little site fidelity and 
likely move within their home range in response to patchy 
concentrations of nearshore prey (Defran and Weller, 1999, Bearzi et 
al., 2009). Oceanographic events may influence the distribution and 
residency patterns of dolphins (Hansen and Defran, 1990, Wells et al., 
1990). In southern California, coastal bottlenose dolphins are 
typically found within 250 m of the shoreline (Hansen and Defran, 
1993).
    Bottlenose dolphin sightings are not common in Oceanside Harbor but 
do occur, typically within the outer surge basin of the harbor and, 
rarely, within the inner harbor.

Common Dolphin (Long-Beaked and Short-Beaked)

    Short-beaked common dolphins (California/Oregon/Washington stock) 
are the most abundant cetacean off of California and are widely 
distributed between the coast and approximately 556 km offshore. In 
contrast, long-beaked common dolphins (California stock) are considered 
a nearshore species and generally occur within 92.6 km of shore. Both 
stocks may shift their distributions seasonally and annually in 
response to oceanographic conditions and prey availability (Carretta et 
al., 2023). Long-beaked common dolphins tend to prefer shallower, 
warmer waters as compared to the short-beaked common dolphin (Perrin, 
2009), yet both stocks appear to be more abundant in coastal waters 
during warm-water months (Bearzi, 2005).
    While there is no occurrence data for common dolphin in Oceanside 
Harbor, they are rare visitors to the northern portion of San Diego Bay 
and could be expected to be rare visitors within the outer portion of 
Oceanside Harbor.

Pacific White-Sided Dolphin

    Pacific white-sided dolphins (California stock) are endemic to 
temperate waters of the North Pacific Ocean, and are the most abundant 
pelagic species of dolphin in the region (Carretta et al., 2023). Off 
the U.S. West Coast, Pacific white-sided dolphins occur primarily in 
shelf and slope waters. Sighting patterns from aerial and shipboard 
surveys conducted in California, Oregon, and Washington suggest 
seasonal north-south movements, with animals found primarily off 
California during colder water months and shifting northward into 
Oregon and Washington as water temperatures increase in late spring and 
summer (Green et al., 1992, Green et al., 1993, Forney and Barlow, 
1998, Carretta et al., 2023). Pacific white-sided dolphins are highly 
social and commonly occur in groups of less than a hundred, although 
groups of several thousands of individuals have been observed. They 
often associate with Risso's dolphins and short-beaked common dolphins, 
and occasionally feed in association with California sea lions and 
mixed species aggregations of seabirds.
    No data of Pacific white-sided dolphin occurrence within Oceanside 
Harbor exists but, as they do occur in the waters of southern 
California, they could enter the outer portion of Oceanside Harbor.

California Sea Lion

    California sea lions occur from Vancouver Island, British Columbia, 
to the southern tip of Baja California, Mexico. Habitat use and 
distribution varies with sex and reproductive stage, and sea lions 
breed on the offshore islands of southern California, western Baja 
California, and the Gulf of California from May through July (Heath and 
Perrin, 2009, Lowry et al., 2017). Adult males may haul out on land to 
breed and defend territory from mid-May through late July. Adult males 
and females are known to haul out more often during warm-water months.
    California sea lions are commonly seen in the proposed project area 
and generally in and around Oceanside Harbor on a pinniped haulout 
float, buoys, rocks, and other structures throughout the harbor (Merkel 
and Associates, Inc., 2023). Beyond these structures, there are no 
known natural haulout locations near the proposed action area. 
Abundance in the proposed project area varies substantially through

[[Page 83086]]

time, with variability also being driven by food availability and 
breeding season movements (pers. comm. Oceanside Harbor Department). 
California sea lions in Oceanside Harbor are typically concentrated 
around the pinniped float approximately 21 m north of the end of the 
existing fishing pier in the proposed project area. This structure was 
installed several years ago to attract sea lions away from docks and 
boats (see Figure 2-1 in application). The Harbor Department noted that 
the pinniped float varies from being completely full (approximately 100 
animals or more) to completely empty. Prior to in-water activity, the 
pinniped float would be relocated by the Oceanside Harbor Department 
when no sea lions or other marine mammals are present to minimize 
attraction of sea lions to the proposed work area during construction.
    California sea lions experienced an Unusual Mortality Event (UME), 
not correlated to an El Ni[ntilde]o event, from 2013-2017 (Carretta et 
al., 2023). Pup and juvenile age classes experienced high mortality 
during this time, likely attributed to a lack of prey availability, 
specifically Pacific sardines (Sardinops sagax). California sea lions 
are also susceptible to the algal neurotoxin domoic acid (Carretta et 
al., 2023), which is expected to cause future mortalities among 
California sea lions due to the prevalence of harmful algal blooms 
within their habitat, as evidenced by recent stranding events along 
parts of the Southern California coast in summer 2023.

Harbor Seal

    Harbor seals are distributed from Baja California, Mexico, to the 
eastern Aleutian Islands of Alaska (Harvey and Goley, 2011). Harbor 
seals do not make extensive pelagic migrations but may travel hundreds 
of kilometers to find food or suitable breeding areas (Harvey and 
Goley, 2011, Carretta et al., 2023). Seals primarily haul out on remote 
mainland and island beaches, reefs, and estuary areas. At haulout 
sites, they congregate to rest, socialize, breed, and molt. In 
California, there are approximately 500 haulout sites along the 
mainland and on offshore islands, including intertidal sandbars, rocky 
shores, and beaches (Hanan, 1996, Lowry et al., 2008).
    Harbor seals are present within Oceanside Harbor, primarily in the 
outer surge basin and not typically within the inner harbor (Merkel and 
Associates, Inc., 2023). Harbor seals may haul out on the pinniped 
float, rocks, buoys, or other structures within the harbor.

Northern Elephant Seal

    Northern elephant seals breed and give birth in California and Baja 
California, mainly on offshore islands during the months of December 
through March (Stewart and Huber, 1993, Stewart et al., 1994, Carretta 
et al., 2023). Molting season takes place from March to August. In 
between the spring/summer molting season and winter breeding season, 
northern elephant seals migrate north, exhibiting spatial segregation 
in foraging areas in the Gulf of Alaska, western Aleutian Islands, and 
central North Pacific Ocean to feeding grounds (Carretta et al., 2023). 
Northern elephant seal populations in the United States and Mexico have 
recovered after being hunted to near extinction (Stewart et al., 1994) 
and undergoing a severe population bottleneck, leading to a loss of 
genetic diversity, that resulted in the population being reduced to an 
estimated 10-30 individuals (Hoelzel et al., 2002, Carretta et al., 
2023). There are two distinct populations of northern elephant seals, 
including a breeding population in Baja California, Mexico, and a 
breeding population on U.S. islands off of California. Northern 
elephant seals in the region could be from either population (Carretta 
et al., 2023).
    Northern elephant seals rarely occur in the Southern California 
Bight and are not expected to occur in Oceanside Harbor. However, given 
the species has been sighted along the southern California coast in 
recent years, potentially due to the continuing long-term increase in 
the population of northern elephant seals (Lowry et al., 2020), there 
is a possibility of occurrence in the project area.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Not all marine mammal species have equal 
hearing capabilities (e.g., Richardson et al., 1995, Wartzok and 
Ketten, 1999, Au and Hastings, 2008). To reflect this, Southall et al. 
(2007, 2019) recommended that marine mammals be divided into hearing 
groups based on directly measured (behavioral or auditory evoked 
potential techniques) or estimated hearing ranges (behavioral response 
data, anatomical modeling, etc.). Note that no direct measurements of 
hearing ability have been successfully completed for mysticetes (i.e., 
low-frequency cetaceans). Subsequently, NMFS (2018) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) was retained. Marine mammal hearing 
groups and their associated hearing ranges are provided in table 3.

                  Table 3--Marine Mammal Hearing Groups
                              [NMFS, 2018]
------------------------------------------------------------------------
               Hearing group                 Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen         7 Hz to 35 kHz.
 whales).
Mid-frequency (MF) cetaceans (dolphins,      150 Hz to 160 kHz.
 toothed whales, beaked whales, bottlenose
 whales).
High-frequency (HF) cetaceans (true          275 Hz to 160 kHz.
 porpoises, Kogia, river dolphins,
 Cephalorhynchid, Lagenorhynchus cruciger &
 L. australis).
Phocid pinnipeds (PW) (underwater) (true     50 Hz to 86 kHz.
 seals).
Otariid pinnipeds (OW) (underwater) (sea     60 Hz to 39 kHz.
 lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on ~65 dB threshold from normalized
  composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al., 2007) and PW pinniped (approximation).


[[Page 83087]]

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006, Kastelein et al., 2009, Reichmuth et al., 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section provides a discussion of the ways in which components 
of the specified activity may impact marine mammals and their habitat. 
The Estimated Take of Marine Mammals section later in this document 
includes a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The Negligible Impact Analysis 
and Determination section considers the content of this section, the 
Estimated Take of Marine Mammals section, and the Proposed Mitigation 
section, to draw conclusions regarding the likely impacts of these 
activities on the reproductive success or survivorship of individuals 
and whether those impacts are reasonably expected to, or reasonably 
likely to, adversely affect the species or stock through effects on 
annual rates of recruitment or survival.
    Acoustic effects on marine mammals during the specified activities 
can occur from impact pile driving and vibratory pile driving and 
removal. The effects of underwater noise from the City of Oceanside's 
proposed activities have the potential to result in Level B harassment 
of marine mammals in the project area.

Description of Sound Sources

    The marine soundscape is comprised of both ambient and 
anthropogenic sounds. Ambient sound is defined as the all-encompassing 
sound in a given place and is usually a composite of sound from many 
sources both near and far (ANSI, 1995). The sound level of an area is 
defined by the total acoustical energy being generated by known and 
unknown sources. These sources may include physical (e.g., waves, wind, 
precipitation, earthquakes, ice, atmospheric sound), biological (e.g., 
sounds produced by marine mammals, fish, and invertebrates), and 
anthropogenic sound (e.g., vessels, dredging, aircraft, construction).
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor, and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, ambient sound levels can be expected 
to vary widely over both coarse and fine spatial and temporal scales. 
Sound levels at a given frequency and location can vary by 10-20 dB 
from day to day (Richardson et al., 1995). The result is that, 
depending on the source type and its intensity, sound from the 
specified activities may be a negligible addition to the local 
environment or could form a distinctive signal that may affect marine 
mammals.
    In-water construction activities associated with the proposed 
project would include vibratory pile extraction and vibratory pile 
installation, and, potentially, impact pile installation. The sounds 
produced by these activities fall into one of two general sound types: 
impulsive and non-impulsive. Impulsive sounds (e.g., explosions, sonic 
booms, impact pile driving) are typically transient, brief (less than 1 
second), broadband, and consist of high peak sound pressure with rapid 
rise time and rapid decay (ANSI, 1986, NIOSH, 1998, NMFS, 2018). Non-
impulsive sounds (e.g., machinery operations such as drilling or 
dredging, vibratory pile driving, underwater chainsaws, and active 
sonar systems) can be broadband, narrowband, or tonal, brief or 
prolonged (continuous or intermittent), and typically do not have the 
high peak sound pressure with raid rise/decay time that impulsive 
sounds do (ANSI, 1995, NIOSH, 1998, NMFS, 2018). The distinction 
between these two sound types is important because they have differing 
potential to cause physical effects, particularly with regard to 
hearing (e.g., Ward, 1997).
    Two types of hammers would be used on this project, vibratory and, 
if necessary, impact. Vibratory hammers install piles by vibrating them 
and allowing the weight of the hammer to push them into the sediment. 
Vibratory hammers produce non-impulsive, continuous sounds. Vibratory 
hammering generally produces sound pressure levels (SPLs) 10-20 dB 
lower than impact pile driving of the same-sized pile (Oestman et al., 
2009). Rise time is slower, reducing the probability and severity of 
injury, and sound energy is distributed over a greater amount of time 
(Nedwell and Edwards, 2002, Carlson et al., 2005). Impact hammers 
operate by repeatedly dropping and/or pushing a heavy piston onto a 
pile to drive the pile into the substrate. Sound generated by impact 
hammers is considered impulsive.
    The likely or possible impacts of the City of Oceanside's proposed 
activities on marine mammals could be generated from both non-acoustic 
and acoustic stressors. Potential non-acoustic stressors include the 
physical presence of the equipment, vessels, and personnel; however, we 
expect that any animals that approach the project site close enough to 
be harassed due to the presence of equipment or personnel would be 
within the Level B harassment zones from pile removal or driving and 
would already be subject to harassment from the in-water activities. 
Therefore, any impacts to marine mammals are expected to primarily be 
acoustic in nature. Acoustic stressors are generated by heavy equipment 
operation during pile driving activities (i.e., impact and vibratory 
pile driving and removal).

Acoustic Impacts

    The introduction of anthropogenic noise into the aquatic 
environment from pile driving equipment is the primary means by which 
marine mammals may be harassed from the City of Oceanside's specified 
activities. In general, animals exposed to natural or anthropogenic 
sound may experience physical and psychological effects, ranging in 
magnitude from none to severe (Southall et al., 2007). Generally, 
exposure to pile driving and removal and other construction noise has 
the potential to result in auditory threshold shifts (TS) and 
behavioral reactions (e.g., avoidance, temporary cessation of foraging 
and vocalizing, changes in dive behavior). Exposure to anthropogenic 
noise can also lead to non-observable physiological responses, such as 
an increase in stress hormones. Additional noise in a marine mammal's 
habitat can mask acoustic cues used by marine mammals to carry out 
daily functions, such as communication and predator and prey detection. 
The effects of pile driving and construction noise on marine mammals 
are dependent on several factors including, but not limited to, sound 
type (e.g., impulsive vs. non-impulsive), the species, age and sex 
class (e.g., adult male vs. mother with calf), duration of exposure, 
the distance between the pile and the animal, received levels, behavior 
at time of exposure, and previous history with exposure (Wartzok et 
al., 2004, Southall et al., 2007). Here we discuss physical auditory 
effects (threshold shifts)

[[Page 83088]]

followed by behavioral effects and potential impacts on habitat.
    NMFS defines a noise-induced TS as a change, usually an increase, 
in the threshold of audibility at a specified frequency or portion of 
an individual's hearing range above a previously established reference 
level (NMFS, 2018). The amount of TS is customarily expressed in dB and 
TS can be permanent or temporary. As described in NMFS (2018), there 
are numerous factors to consider when examining the consequence of TS, 
including, but not limited to, the signal temporal pattern (e.g., 
impulsive or non-impulsive), likelihood an individual would be exposed 
for a long enough duration or to a high enough level to induce a TS, 
the magnitude of the TS, time to recovery (seconds to minutes or hours 
to days), the frequency range of the exposure (i.e., spectral content), 
the hearing and vocalization frequency range of the exposed species 
relative to the signal's frequency spectrum (i.e., how animal uses 
sound within the frequency band of the signal) (Kastelein et al., 
2014b), and the overlap between the animal and the source (e.g., 
spatial, temporal, and spectral).
    Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent, 
irreversible increase in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS, 2018). Available data 
from humans and other terrestrial mammals indicate that a 40 dB TS 
approximates PTS onset (see Ward et al., 1958, Ward et al., 1959, Ward, 
1960, Kryter et al., 1966, Miller, 1974, Ahroon et al., 1996, Henderson 
et al., 2008). PTS levels for marine mammals are estimates because 
there are limited empirical data measuring PTS in marine mammals (e.g., 
Kastak et al., 2008), largely due to the fact that, for various ethical 
reasons, experiments involving anthropogenic noise exposure at levels 
inducing PTS are not typically pursued or authorized (NMFS, 2018).
    Temporary Threshold Shift (TTS)--TTS is a temporary, reversible 
increase in the threshold of audibility at a specified frequency or 
portion of an individual's hearing range above a previously established 
reference level (NMFS, 2018). Based on data from cetacean TTS 
measurements (see Southall et al., 2007), a TTS of 6 dB is considered 
the minimum TS clearly larger than any day-to-day or session-to-session 
variation in a subject's normal hearing ability (Schlundt et al., 2000, 
Finneran et al., 2000, FInneran et al., 2002). As described in Finneran 
(2016), marine mammal studies have shown the amount of TTS increases 
with cumulative sound exposure level (SEL<INF>cum</INF>) in an 
accelerating fashion: At low exposures with lower SEL<INF>cum</INF>, 
the amount of TTS is typically small and the growth curves have shallow 
slopes. At exposures with higher SEL<INF>cum</INF>, the growth curves 
become steeper and approach linear relationships with the noise SEL.
    Depending on the degree (elevation of threshold in dB), duration 
(i.e., recovery time), and frequency range of TTS, and the context in 
which it is experienced, TTS can have effects on marine mammals ranging 
from discountable to serious (similar to those discussed in auditory 
Masking, below). For example, a marine mammal may be able to readily 
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal 
is traveling through the open ocean, where ambient noise is lower and 
there are not as many competing sounds present. Alternatively, a larger 
amount and longer duration of TTS sustained during time when 
communication is critical for successful mother/calf interactions could 
have more serious impacts. We note that reduced hearing sensitivity as 
a simple function of aging has been observed in marine mammals, as well 
as humans and other taxa (Southall et al., 2007), so we can infer that 
strategies exist for coping with this condition to some degree, though 
likely not without cost.
    Currently, TTS data only exist for four species of cetaceans 
(bottlenose dolphin, beluga whale (Delphinapterus leucas), harbor 
porpoise (Phocoena phocoena), Yangtze finless porpoise (Neophocoena 
asiaeorientalis)) and five species of pinnipeds exposed to a limited 
number of sound sources (i.e., tones and octave-band noise) in 
laboratory settings (Finneran, 2015). TTS was not observed in trained 
spotted seals (Phoca largha) and ringed seals (Pusa hispida) exposed to 
impulsive noise at levels matching previous predictions of TTS onset 
(Reichmuth et al., 2016). In general, harbor seals and harbor porpoises 
have a lower TTS onset than other measured pinniped or cetacean species 
(Finneran, 2015). At low frequencies, onset-TTS exposure levels are 
higher compared to those in the region of best sensitivity (i.e., a low 
frequency noise would need to be louder to cause TTS onset when TTS 
exposure level is higher), as shown for harbor porpoises and harbor 
seals (Kastelein et al., 2019b, Kastelein et al., 2019a, Kastelein et 
al., 2020a, Kastelein et al., 2020b). In addition, TTS can accumulate 
across multiple exposures but the resulting TTS will be less than the 
TTS from a single, continuous exposure with the same SEL (Mooney et 
al., 2009, Finneran et al., 2010, Kastelein et al., 2014a, Kastelein et 
al., 2015). This means that TTS predictions based on the total 
SEL<INF>cum</INF> will overestimate the amount of TTS from intermittent 
exposures such as sonars and impulsive sources.
    The potential for TTS from impact pile driving exists. After 
exposure to playbacks of impact pile driving sounds (rate 2,760 
strikes/hour) in captivity, mean TTS increased from 0 dB after a 15 
minute exposure to 5 dB after a 360 minute exposure; recovery occurred 
within 60 minutes (Kastelein et al., 2016). Additionally, the existing 
marine mammal TTS data come from a limited number of individuals within 
these species. No data are available on noise-induced hearing loss for 
mysticetes. Nonetheless, what we considered is the best available 
science. For summaries of data on TTS in marine mammals or for further 
discussion of TTS onset thresholds, please see Southall et al. (2007), 
Southall et al. (2019), Finneran and Jenkins (2012), Finneran (2015), 
and table 5 in NMFS (2018).
    Proposed activities for this project include vibratory pile driving 
and vibratory pile removal and, potentially, impact pile driving. There 
would likely be pauses in activities producing the sound during each 
day and, given these pauses and the fact that many marine mammals would 
likely be moving through the project areas and not remaining for 
extended periods of time, the potential for TS declines.
    Behavioral Harassment--Exposure to noise from pile driving and 
removal also has the potential to behaviorally disturb marine mammals. 
Available studies show wide variation in response to underwater sound; 
therefore, it is difficult to predict specifically how any given sound 
in a particular instance might affect marine mammals perceiving the 
signal. If a marine mammal does react briefly to an underwater sound by 
changing its behavior or moving a small distance, the impacts of the 
change are unlikely to be significant to the individual, let alone the 
stock or population. However, if a sound source displaces marine 
mammals from an important feeding or breeding area for a prolonged 
period, impacts on individuals and populations could be significant 
(e.g., Council, 2005, Lusseau and Bejder, 2007, Weilgart, 2007b).
    Disturbance may result in changing durations of surfacing and 
dives, number of blows per surfacing, or moving direction and/or speed;

[[Page 83089]]

reduced/increased vocal activities; changing/cessation of certain 
behavioral activities (such as socializing or feeding); visible startle 
response or aggressive behavior (such as tail/fluke slapping or jaw 
clapping); or avoidance of areas where sound sources are located. 
Pinnipeds may increase their haulout time, possibly to avoid in-water 
disturbance (Thorson and Reyff, 2006). Behavioral responses to sound 
are highly variable and context-specific and any reactions depend on 
numerous intrinsic and extrinsic factors (e.g., species, state of 
maturity, experience, current activity, reproductive state, auditory 
sensitivity, time of day), as well as the interplay between factors 
(e.g., Richardson et al., 1995, Wartzok et al., 2004, Southall et al., 
2007, Weilgart, 2007a, Archer et al., 2010, Southall et al., 2021). 
Behavioral reactions can vary not only among individuals but also 
within an individual depending on previous experience with a sound 
source, context, and numerous other factors (Ellison et al., 2012), and 
can vary depending on characteristics associated with the sound source 
(e.g., whether it is moving or stationary, number of sources, distance 
from the source). In general, pinnipeds seem more tolerant of, or at 
least habituate more quickly to, potentially disturbing underwater 
sound than do cetaceans, and generally seem to be less responsive to 
exposure to industrial sound than most cetaceans. Please see Appendices 
B and C of Southall et al. (2007) as well as Nowacek et al. (2007), 
Ellison et al. (2012), and Gomez et al. (2016) for a review of studies 
involving marine mammal behavioral responses to sound.
    Disruption of feeding behavior can be difficult to correlate with 
anthropogenic sound exposure, so it is usually inferred by observed 
displacement from known foraging areas, the appearance of secondary 
indicators (e.g., bubble nets or sediment plumes), or changes in dive 
behavior. As for other types of behavioral response, the frequency, 
duration, and temporal pattern of signal presentation, as well as 
differences in species sensitivity, are likely contributing factors to 
differences in response in any given circumstance (e.g., Croll et al., 
2001, Nowacek et al., 2004, Madsen et al., 2006, Yazvenko et al., 2007, 
Melcon et al., 2012). In addition, behavioral state of the animal plays 
a role in the type and severity of a behavioral response, such as 
disruption to foraging (e.g., Sivle et al., 2016, Wensveen et al., 
2017). A determination of whether foraging disruptions incur fitness 
consequences would require information on, or estimates of, the 
energetic requirements of the affected individuals and the relationship 
between prey availability, foraging effort and success, and the life 
history stage of the animal (Goldbogen et al., 2013).
    Stress responses--An animal's perception of a threat may be 
sufficient to trigger stress responses consisting of some combination 
of behavioral responses, autonomic nervous system responses, 
neuroendocrine responses, or immune responses (e.g., Selye, 1950, 
Moberg, 2000). In many cases, an animal's first and sometimes most 
economical (in terms of energetic costs) response is behavioral 
avoidance of the potential stressor. Autonomic nervous system responses 
to stress typically involve changes in heart rate, blood pressure, and 
gastrointestinal activity. These responses have a relatively short 
duration and may or may not have a significant long-term effect on an 
animal's fitness.
    Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that 
are affected by stress--including immune competence, reproduction, 
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been 
implicated in failed reproduction, altered metabolism, reduced immune 
competence, and behavioral disturbance (e.g., Moberg, 1987, Blecha, 
2000). Increases in the circulation of glucocorticoids are also equated 
with stress (Romano et al., 2004).
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and ``distress'' is the cost of 
the response. During a stress response, an animal uses glycogen stores 
that can be quickly replenished once the stress is alleviated. In such 
circumstances, the cost of the stress response would not pose serious 
fitness consequences. However, when an animal does not have sufficient 
energy reserves to satisfy the energetic costs of a stress response, 
energy resources must be diverted from other functions. This state of 
distress will last until the animal replenishes its energetic reserves 
sufficient to restore normal function.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses are well-studied through 
controlled experiments for both laboratory and free-ranging animals 
(e.g., Holberton et al., 1996, Hood et al., 1998, Jessop et al., 2003, 
Krausman et al., 2004, Lankford et al., 2005). Stress responses due to 
exposure to anthropogenic sounds or other stressors and their effects 
on marine mammals have also been reviewed (Fair and Becker, 2000, 
Romano et al., 2002b) and, more rarely, studied in wild populations 
(e.g., Romano et al., 2002a). For example, Rolland et al. (2012) found 
that noise reduction from reduced vessel traffic in the Bay of Fundy 
was associated with decreased stress in North Atlantic right whales 
(Eubalaena glacialis). These and other studies lead to a reasonable 
expectation that some marine mammals will experience physiological 
stress responses upon exposure to acoustic stressors and that it is 
possible that some of these would be classified as ``distress.'' In 
addition, any animal experiencing TTS would likely also experience 
stress responses (NRC, 2003), however, distress is an unlikely result 
of the proposed project based on observations of marine mammals during 
previous, similar projects in the region.
    Masking--Sound can disrupt behavior through masking, or interfering 
with, an animal's ability to detect, recognize, or discriminate between 
acoustic signals of interest (e.g., those used for intraspecific 
communication and social interactions, prey detection, predator 
avoidance, navigation) (Richardson et al., 1995). Masking occurs when 
the receipt of a sound is interfered with by another coincident sound 
at similar frequencies and at similar or higher intensity, and may 
occur whether the sound is natural (e.g., snapping shrimp, wind, waves, 
precipitation) or anthropogenic (e.g., pile driving, shipping, sonar, 
seismic exploration) in origin. The ability of a noise source to mask 
biologically important sounds depends on the characteristics of both 
the noise source and the signal of interest (e.g., signal-to-noise 
ratio, temporal variability, direction), in relation to each other and 
to an animal's hearing abilities (e.g., sensitivity, frequency range, 
critical ratios, frequency discrimination, directional discrimination, 
age or TTS hearing loss), and existing ambient noise and propagation 
conditions. Masking of natural sounds can result when human activities 
produce high levels of background sound at frequencies important to 
marine mammals. Conversely, if the background level of underwater sound 
is high (e.g., on a day with strong wind and high waves), an 
anthropogenic sound source would not be detectable as far away as would 
be possible under quieter conditions and would itself be masked. The 
masking of communication signals by anthropogenic noise may be 
considered as a reduction in the

[[Page 83090]]

communication space of animals (e.g., Clark et al., 2009) and may 
result in energetic or other costs as animals change their vocalization 
behavior (e.g., Miller et al., 2000, Foote et al., 2004, Parks et al., 
2007, Di Iorio and Clark, 2010, Holt et al., 2009). Oceanside Harbor is 
used by commercial and recreational vessels, and background sound 
levels in the area are already elevated. Due to the transient nature of 
marine mammals to move and avoid disturbance, masking is not likely to 
have long-term impacts on marine mammal species within the proposed 
project area.
    Airborne Acoustic Effects--Pinnipeds that occur near the project 
site could be exposed to airborne sounds associated with pile driving 
and removal that have the potential to cause behavioral harassment, 
depending on their distance from piling activities. Cetaceans are not 
expected to be exposed to airborne sounds that would result in 
harassment as defined under the MMPA.
    Airborne noise would primarily be an issue for pinnipeds that are 
swimming or hauled out near the project site within the range of noise 
levels elevated above the acoustic criteria. We recognize that 
pinnipeds in the water could be exposed to airborne sound that may 
result in behavioral harassment when looking with their heads above 
water. Most likely, airborne sound would cause behavioral responses 
similar to those discussed above in relation to underwater sound. For 
instance, anthropogenic sound could cause hauled out pinnipeds to 
exhibit changes in their normal behavior, such as reduction in 
vocalizations, or cause them to temporarily abandon the area and move 
further from the source. However, these animals would likely previously 
have been ``taken'' because of exposure to underwater sound above the 
behavioral harassment thresholds, which are generally larger than those 
associated with airborne sound. Thus, the behavioral harassment of 
these animals is already accounted for in these estimates of potential 
take. Therefore, we do not believe that authorization of incidental 
take resulting from airborne sound for pinnipeds is warranted, and 
airborne sound is not discussed further.

Marine Mammal Habitat Effects

    The City of Oceanside's proposed construction activities could have 
localized, temporary impacts on marine mammal habitat, including prey, 
by increasing in-water SPLs and slightly decreasing water quality. 
Increased noise levels may affect acoustic habitat (see Masking above) 
and adversely affect marine mammal prey in the vicinity of the project 
area (see discussion below). During impact and vibratory pile driving 
or removal, elevated levels of underwater noise would ensonify the 
project area where both fishes and mammals occur and could affect 
foraging success. Additionally, marine mammals may avoid the area 
during construction, however, displacement due to noise is expected to 
be temporary and is not expected to result in long-term effects to the 
individuals or populations. Construction activities are expected to be 
of short duration (6 non-consecutive days) and would likely have 
temporary impacts on marine mammal habitat through increases in 
underwater and airborne sound.
    A temporary and localized increase in turbidity near the seafloor 
would occur in the immediate area surrounding the area where piles are 
installed or removed, for example, if high-pressure water jetting is 
used. In general, turbidity associated with pile driving is localized 
to an approximately 7.6 m radius around the pile (Everitt et al., 
1980). Cetaceans are not expected to be close enough to the pile 
driving areas to experience effects of turbidity, and any pinnipeds 
could avoid localized areas of turbidity. Therefore, we expect the 
impact from increased turbidity levels to be discountable to marine 
mammals and do not discuss it further.
    In-Water Construction Effects on Potential Foraging Habitat--The 
area likely impacted by the proposed action is relatively small 
compared to the total available habitat in the area within and outside 
the harbor. The proposed project area is highly influenced by 
anthropogenic activities and provides limited foraging habitat for 
marine mammals. Furthermore, pile driving and removal at the proposed 
project site would not obstruct long-term movements or migration of 
marine mammals.
    Avoidance of the immediate area by potential prey (i.e., fish) due 
to the temporary loss of foraging habitat is also possible. The 
duration of fish and marine mammal avoidance of this area after pile 
driving stops is unknown but a rapid return to normal recruitment, 
distribution, and behavior is anticipated. Any behavioral avoidance by 
prey of the disturbed area would still leave significantly large areas 
of potential foraging habitat in the nearby vicinity, primarily outside 
the harbor.
    In-water Construction Effects on Potential Prey--Sound may affect 
marine mammals through impacts on the abundance, behavior, or 
distribution of prey species (e.g., crustaceans, cephalopods, fish, 
zooplankton, other marine mammals). Marine mammal prey varies by 
species, season, and location. Here, we describe studies regarding the 
effects of noise on known marine mammal prey.
    Fish utilize the soundscape and components of sound in their 
environment to perform important functions such as foraging, predator 
avoidance, mating, and spawning (Zelick et al., 1999, Fay, 2009). 
Depending on their hearing anatomy and peripheral sensory structures, 
which vary among species, fishes hear sounds using pressure and 
particle motion sensitivity capabilities and detect the motion of 
surrounding water (Fay et al., 2008). The potential effects of noise on 
fishes depends on the overlapping frequency range, distance from the 
sound source, water depth of exposure, and species-specific hearing 
sensitivity, anatomy, and physiology. Key impacts to fishes may include 
behavioral responses, hearing damage, barotrauma (pressure-related 
injuries), and mortality.
    Fish react to sounds which are especially strong and/or 
intermittent low-frequency sounds, and behavioral responses such as 
flight or avoidance are the most likely effects. Short duration, sharp 
sounds can cause overt or subtle changes in fish behavior and local 
distribution. The reaction of fish to noise depends on the 
physiological state of the fish, past exposures, motivation (e.g., 
feeding, spawning, migration), and other environmental factors. 
Hastings and Popper (2005) identified several studies that suggest fish 
may relocate to avoid certain areas of sound energy. Additional studies 
have documented effects of pile driving on fish, several of which are 
based on studies in support of large, multiyear bridge construction 
projects (e.g., Scholik and Yan, 2001, Popper and Hastings, 2009). Many 
studies have demonstrated that impulse sounds might affect the 
distribution and behavior of some fishes, potentially impacting 
foraging opportunities or increasing energetic costs (e.g., Pearson et 
al., 1992, Skalski et al., 1992, Santulli et al., 1999, Fewtrell and 
McCauley, 2012, Paxton et al., 2017). In response to pile driving, 
Pacific sardines and northern anchovies (Engraulis mordax) may exhibit 
an immediate startle response to individual strikes but return to 
``normal'' pre-strike behavior following the conclusion of pile driving 
with no evidence of injury as a result (see NAVFAC, 2014). However, 
some studies have shown no or slight reaction to impulse sounds (e.g., 
Wardle et al., 2001, Popper et al., 2005, Jorgenson and Gyselman, 2009, 
Pe[ntilde]a et al., 2013).

[[Page 83091]]

    SPLs of sufficient strength have been known to cause injury to fish 
and fish mortality. However, in most fish species, hair cells in the 
ear continuously regenerate and loss of auditory function likely is 
restored when damaged cells are replaced with new cells. Halvorsen et 
al. (2012b) showed that a TTS of 4-6 dB was recoverable within 24 hours 
for one species. Impacts would be most severe when the individual fish 
is close to the source and when the duration of exposure is long. 
Injury caused by barotrauma can range from slight to severe and can 
cause death, and is most likely for fish with swim bladders. Barotrauma 
injuries have been documented during controlled exposure to impact pile 
driving (Halvorsen et al., 2012a, Casper et al., 2013) and the greatest 
potential effect on fish during the proposed project would occur during 
impact pile driving, if it is required. However, the duration of impact 
pile driving would be limited to a contingency in the event that 
vibratory driving does not satisfactorily install the pile depending on 
observed soil resistance. In-water construction activities would only 
occur during daylight hours allowing fish to forage and transit the 
project area at night. Vibratory pile driving may elicit behavioral 
reactions from fish such as temporary avoidance of the area but is 
unlikely to cause injuries to fish or have persistent effects on local 
fish populations. In addition, it should be noted that the area in 
question is low-quality habitat since it is already developed and 
experiences anthropogenic noise from vessel traffic.
    The most likely impact to fishes from pile driving and removal and 
construction activities at the project area would be temporary 
behavioral avoidance of the area. The duration of fish avoidance of 
this area after pile driving stops is unknown but a rapid return to 
normal recruitment, distribution, and behavior is anticipated. In 
general, impacts to marine mammal prey species are expected to be minor 
and temporary. Further, it is anticipated that preparation activities 
for pile driving or removal (i.e., positioning of the hammer) and upon 
initial startup of devices would cause fish to move away from the 
affected area where injuries may occur. Therefore, relatively small 
portions of the proposed project area would be affected for short 
periods of time, and the potential for effects on fish to occur would 
be temporary and limited to the duration of sound-generating 
activities.
    In summary, given the short daily duration of sound associated with 
individual pile driving events and the relatively small area being 
affected, pile driving activities associated with the proposed action 
are not likely to have a permanent, adverse effect on any fish habitat 
or populations of fish species. Any behavioral avoidance by fish of the 
disturbed area would still leave significantly large potential areas 
for fish and marine mammal foraging in the nearby vicinity. Thus, we 
conclude that impacts of the specified activities are not likely to 
have more than short-term adverse effects on any prey habitat or 
populations of prey species. Further, any impacts to marine mammal 
habitat are not expected to result in significant or long-term 
consequences for individual marine mammals, or to contribute to adverse 
impacts on their populations.

Estimated Take of Marine Mammals

    This section provides an estimate of the number of incidental takes 
proposed for authorization through this IHA, which will inform both 
NMFS' consideration of ``small numbers,'' and the negligible impact 
determinations.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the MMPA defines ``harassment'' as any act of 
pursuit, torment, or annoyance, which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment); 
or (ii) has the potential to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of behavioral patterns, 
including, but not limited to, migration, breathing, nursing, breeding, 
feeding, or sheltering (Level B harassment).
    Authorized takes would be by Level B harassment only in the form of 
disruption of behavioral patterns for individual marine mammals 
resulting from exposure to the acoustic sources. Based on the nature of 
the activity and the anticipated effectiveness of the mitigation 
measures (i.e., shutdown) discussed in detail below in the Proposed 
Mitigation section, Level A harassment is neither anticipated nor 
proposed to be authorized.
    As described previously, no serious injury or mortality is 
anticipated or proposed to be authorized for this activity. Below we 
describe how the proposed take numbers are estimated.
    For acoustic impacts, generally speaking, we estimate take by 
considering: (1) acoustic thresholds above which NMFS believes the best 
available science indicates marine mammals will be behaviorally 
harassed or incur some degree of permanent hearing impairment; (2) the 
area or volume of water that will be ensonified above these levels in a 
day; (3) the density or occurrence of marine mammals within these 
ensonified areas; and, (4) the number of days of activities. We note 
that while these factors can contribute to a basic calculation to 
provide an initial prediction of potential takes, additional 
information that can qualitatively inform take estimates is also 
sometimes available (e.g., previous monitoring results or average group 
size). Below, we describe the factors considered here in more detail 
and present the proposed take estimates.

Acoustic Thresholds

    NMFS recommends the use of acoustic thresholds that identify the 
received level of underwater sound above which exposed marine mammals 
would be reasonably expected to be behaviorally harassed (equated to 
Level B harassment) or to incur PTS of some degree (equated to Level A 
harassment).
    Level B Harassment--Though significantly driven by received level, 
the onset of behavioral disturbance from anthropogenic noise exposure 
is also informed to varying degrees by other factors related to the 
source or exposure context (e.g., frequency, predictability, duty 
cycle, duration of the exposure, signal-to-noise ratio, distance to the 
source), the environment (e.g., bathymetry, other noises in the area, 
predators in the area), and the receiving animals (hearing, motivation, 
experience, demography, life stage, depth) and can be difficult to 
predict (e.g., Southall et al., 2007, Southall et al., 2021, Ellison et 
al., 2012). Based on what the available science indicates and the 
practical need to use a threshold based on a metric that is both 
predictable and measurable for most activities, NMFS typically uses a 
generalized acoustic threshold based on received level to estimate the 
onset of behavioral harassment. NMFS generally predicts that marine 
mammals are likely to be behaviorally harassed in a manner considered 
to be Level B harassment when exposed to underwater anthropogenic noise 
above root-mean-squared pressure received levels (RMS SPL) of 120 dB 
(referenced to 1 microPascal (re 1 [mu]Pa)) for continuous (e.g., 
vibratory pile driving, drilling) and above RMS SPL 160 dB re 1 [mu]Pa 
for non-explosive impulsive (e.g., seismic airguns) or intermittent 
(e.g., scientific sonar) sources. Generally speaking, Level B 
harassment take estimates based on these behavioral harassment 
thresholds are expected to include any

[[Page 83092]]

likely takes by TTS as, in most cases, the likelihood of TTS occurs at 
distances from the source less than those at which behavioral 
harassment is likely. TTS of a sufficient degree can manifest as 
behavioral harassment as reduced hearing sensitivity and the potential 
reduced opportunities to detect important signals (e.g., conspecific 
communication, predators, prey) may result in changes in behavior 
patterns that would not otherwise occur.
    The City of Oceanside's proposed construction activities includes 
the use of continuous (vibratory pile removal and installation) and, 
potentially, impulsive (impact pile installation) sources, and 
therefore the RMS SPL thresholds of 120 and 160 dB re 1 [mu]Pa are both 
applicable.
    Level A Harassment--NMFS' Technical Guidance for Assessing the 
Effects of Anthropogenic Sound on Marine Mammal Hearing (Version 2.0) 
(Technical Guidance, 2018) identifies dual criteria to assess auditory 
injury (Level A harassment) to five different marine mammal groups 
(based on hearing sensitivity) as a result of exposure to noise from 
two different types of sources (impulsive or non-impulsive). The City 
of Oceanside's proposed activity includes the use of impulsive (impact 
hammer) and non-impulsive (vibratory hammer) sources.
    These thresholds are provided in table 4, below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS' 2018 Technical Guidance, which may be accessed at: 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                     PTS onset acoustic thresholds * (received level)
             Hearing group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB..
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB..
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB..
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB..
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 dB..
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
  calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
  thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
  has a reference value of 1[mu]Pa\2\s. In this table, thresholds are abbreviated to reflect American National
  Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as incorporating
  frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript ``flat'' is
  being included to indicate peak sound pressure should be flat weighted or unweighted within the generalized
  hearing range. The subscript associated with cumulative sound exposure level thresholds indicates the
  designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds) and
  that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could be
  exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible, it
  is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
  exceeded.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that are used in estimating the area ensonified above the 
acoustic thresholds, including source levels and transmission loss (TL) 
coefficient.
    Pile driving activities using an impact hammer as well as a 
vibratory hammer would generate underwater noise that could result in 
disturbance to marine mammals near the project area. A review of 
underwater sound measurements for similar projects was conducted to 
estimate the near-source sound levels for impact and vibratory pile 
driving and vibratory extraction. Source levels for proposed removal 
and installation activities derived from this review are shown in table 
5.

                                                          Table 5--Project Sound Source Levels
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Pile size (inch,    Peak SPL dB re   RMS SPL dB re    SEL dB re 1
              Activity                       Method               material)         1 [mu]Pa \1\    1 [mu]Pa \1\     [mu]Pa \1\            Source
--------------------------------------------------------------------------------------------------------------------------------------------------------
Extraction.........................  Vibratory............  16, concrete \2\.....             N/A             163             N/A  NAVFAC SW, 2022.
Installation.......................  Vibratory............  18, steel............             196             158             N/A  Caltrans, 2020.
Installation.......................  Impact...............  18, steel \3\........             200             185             175  Caltrans, 2020.
Installation.......................  Vibratory............  10, steel \4\........             171             155             N/A  Illingworth and
                                                                                                                                    Rodkin, 2007.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: All 18-inch round steel piles will be installed using both vibratory and impact driving, therefore, the total number of 18-inch piles proposed for
  use is 18. Use of 10-inch piles will be as temporary support, and will be driven and removed in the same day as the permanent 18-inch piles.
\1\ As measured, or calculated, at 10 m (33 ft).
\2\ Proxy source levels provided by NMFS from Pier 6 Replacement Project, San Diego Bay (NAVFAC SW, 2022).
\3\ Analysis of pooled reported data provided by NMFS (Caltrans, 2020).
\4\ In the absence of information on vibratory installation of 10-inch round steel piles, source data from 12-inch round steel piles (Illingworth and
  Rodkin, 2007) was used as a proxy source level.

    Level B Harassment Zone--TL is the decrease in acoustic intensity 
as an acoustic pressure wave propagates out from a source. TL 
parameters vary with frequency, temperature, sea conditions, current, 
source and receiver depth, water depth, water chemistry, and bottom 
composition topography. The general formula for underwater TL is:

TL = B * Log10 (R1/R2),

where:
TL = transmission loss in dB;
B = transmission loss coefficient;
R1 = the distance of the modeled SPL from the driven pile; and
R2 = the distance from the driven pile of the

[[Page 83093]]

initial measurement.

    The recommended TL coefficient for most nearshore environments is 
the practical spreading value of 15. This value results in an expected 
propagation environment that would lie between spherical and 
cylindrical spreading loss conditions, known as practical spreading, 
which is the most appropriate assumption for the City of Oceanside's 
proposed activity in the absence of specific modeling and site-specific 
information. Sound propagation in Oceanside Harbor is limited by 
physical structures and substantial sound would be confined within the 
harbor (see Figures 6-1, 6-2 in application). The Level A and Level B 
harassment isopleths for the City of Oceanside's proposed activities 
are shown in table 6.

                               Table 6--Distance to the Level A and Level B Harassment Thresholds for Proposed Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                              Level A         Level A         Level A         Level B
               Activity                         Method              Pile size  (inch,      threshold for   threshold for   threshold for    harassment
                                                                        material)             MF (m)          PW (m)          OW (m)         zone  (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Extraction...........................  Vibratory...............  16, concrete...........             1.2             7.9             0.6           7,356
Installation.........................  Vibratory...............  18, steel..............             0.5             3.7             0.3           3,415
Installation.........................  Impact..................  18, steel..............            11.7           176.7            12.9             100
Installation.........................  Vibratory...............  10, steel..............             0.2             1.3             0.1           2,154
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: for impact pile driving, the single strike SEL was used to calculate distances to Level A harassment thresholds.
Abbreviations: MF = mid-frequency cetaceans, PW = phocid pinnipeds, OW = otariid pinnipeds.

    Level A Harassment Zones--The ensonified area associated with Level 
A harassment is more technically challenging to predict due to the need 
to account for a duration component. Therefore, NMFS developed an 
optional User Spreadsheet tool to accompany the Technical Guidance that 
can be used to relatively simply predict an isopleth distance for use 
in conjunction with marine mammal density or occurrence to help predict 
potential takes. We note that because of some of the assumptions 
included in the methods underlying this optional tool, we anticipate 
that the resulting isopleth estimates are typically going to be 
overestimates of some degree, which may result in an overestimate of 
potential take by Level A harassment. However, this optional tool 
offers the best way to estimate isopleth distances when more 
sophisticated modeling methods are not available or practical. For 
stationary sources (i.e., vibratory and impact piling), the optional 
User Spreadsheet tool predicts the distance at which, if a marine 
mammal remained at that distance for the duration of the activity, it 
would be expected to incur PTS. Inputs used in the optional User 
Spreadsheet tool, and the resulting estimated isopleths, are reported 
in tables 6 and 7. The isopleths generated by the User Spreadsheet used 
the same TL coefficients as the Level B harassment isopleth 
calculations, as indicated above for each activity type. Inputs used in 
the User Spreadsheet (e.g., number of piles per day, duration and/or 
strikes per pile) are presented in table 1. The maximum RMS SPL, SEL, 
and peak SPL are reported in table 7. The cumulative SEL and peak SPL 
were used to calculate Level A harassment isopleths for vibratory pile 
driving and extraction activities, while the single strike SEL value 
was used to calculate Level A harassment isopleths for impact pile 
driving activity.

                                           Table 7--Sound Levels Used for Predicting Underwater Sound Impacts
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                           Single strike
               Activity                         Method              Pile size  (inch,        Duration     Peak SPL dB re   RMS SPL dB re    SEL dB re 1
                                                                        material)           (hours/day)      1 [mu]Pa        1 [mu]Pa      [mu]Pa\2\ sec
--------------------------------------------------------------------------------------------------------------------------------------------------------
Extraction...........................  Vibratory...............  16, concrete...........            1.67             N/A             163             N/A
Installation.........................  Vibratory...............  18, steel..............            1.67             196             158             N/A
Installation.........................  Impact..................  18, steel..............            0.13             200             185             175
Installation.........................  Vibratory...............  10, steel..............            0.67             171             155             N/A
--------------------------------------------------------------------------------------------------------------------------------------------------------

Marine Mammal Occurrence

    In this section we provide information about the occurrence of 
marine mammals, including density or other relevant information which 
will inform the take calculations.
    Bottlenose Dolphin--Bottlenose dolphins can occur at any time of 
year in the waters around Oceanside Harbor. Based on previous 
monitoring (Merkel and Associates, Inc., 2022), an average of 6 
bottlenose dolphins per day were observed with a maximum of 12 
individuals being observed on a single day. This higher peak of 12 
individuals was used to calculate Level B harassment for bottlenose 
dolphin.
    Common Dolphin--Common dolphins are generally abundant in the outer 
coastal waters but are not known to occur regularly in Oceanside 
Harbor. Based on marine mammal monitoring by NAVFAC SW (2015), during 
El Ni[ntilde]o conditions an average of 8.5 common dolphins per day 
(rounded to nine per day) were observed in northwest San Diego Bay. 
This expected daily individual count was used to calculate the take by 
Level B harassment for common dolphins within Oceanside Harbor as no 
local data exists.
    Pacific White-Sided Dolphin--Pacific white-sided dolphins are 
commonly seen offshore of southern California but are not known to 
occur regularly in Oceanside Harbor. Based on the observations 
presented by NAVFAC SW (2015), during El Ni[ntilde]o conditions an 
average of 0.3 Pacific white-sided dolphins per day (rounded to one per 
day) were observed. This expected daily individual count was used to 
calculate the Level B harassment for Pacific white-sided dolphins.
    California Sea Lion--California sea lions are present in Oceanside 
Harbor year-round and numbers vary considerably. The daily estimate 
provided by the Oceanside Harbor Department is over 100 individuals. 
Limited counts from photographs and

[[Page 83094]]

spot counts average approximately 50 individuals and are known to be 
incomplete estimates. Based on the variability in the number of sea 
lions present in the harbor, an estimate of 100 sea lions per day was 
used to estimate take.
    Harbor Seal--Based on marine mammal monitoring by NAVFAC SW (2015), 
during El Ni[ntilde]o conditions an average of 2.5 harbor seals per day 
(rounded to three per day) were observed. This expected daily 
individual count was used to calculate the Level B harassment for 
harbor seals in Oceanside Harbor.
    Northern Elephant Seal--Due to increasing population size of 
northern elephant seals, presence in the Southern California Bight is 
considered a reasonable possibility (Carretta et al., 2023). Based on 
marine mammal monitoring by NAVFAC SW (2015), an average of 0.1 
northern elephant seals per day (rounded to one per day) were observed 
during El Ni[ntilde]o conditions. This expected daily individual count 
was used to calculate the Level B harassment for northern elephant 
seals in Oceanside Harbor.

Take Estimation

    Here we describe how the information provided above is synthesized 
to produce a quantitative estimate of the take that is reasonably 
likely to occur and proposed for authorization.
    No take by Level A harassment is proposed for any species of marine 
mammal due to the small zone sizes for most taxa, and the low 
likelihood that an animal would approach during in-water construction 
or remain within the Level A harassment isopleth long enough to incur 
PTS during the specified activities. Proposed shutdown zones would 
encompass the extent of the estimated Level A harassment isopleths (180 
m for phocid pinnipeds during impact driving, 15 m for all other 
species and activities) and are expected to be effective at avoiding 
Level A harassment for all species. Given the locations of Protected 
Species Observers (PSOs) described in the Proposed Monitoring and 
Reporting section, in conjunction with the City of Oceanside's proposed 
shutdown mitigation measure, NMFS agrees that monitoring and shutdown 
measures are likely to be successful at avoiding take by Level A 
harassment.
    Incidental take by Level B harassment was estimated for each 
species by multiplying the expected average number of individuals per 
day by the number of work days (6 days; table 8). Take estimates for 
each species were calculated by multiplying the estimated site-specific 
abundance of each species by the area of impact where noise levels 
exceed acoustic thresholds for marine mammals during active each type 
of piling activity (vibratory removal, vibratory driving, impact 
driving) and pile size (16 inch concrete, 18 inch steel, 10 inch 
steel). Estimated daily exposures for each species were based on 
evaluation of the potential presence of each marine mammal species 
using historical occurrence from Oceanside Harbor (Merkel and 
Associates, Inc., 2022; Merkel and Associates, Inc., 2023).

Estimated Take = Expected Average Individuals per Day x Number of Work 
Days

    Due to a paucity of marine mammal occurrence data within Oceanside 
Harbor, and with the probability of El Ni[ntilde]o conditions 
persisting throughout 2024 (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml), four species of 
marine mammal (common dolphin, Pacific white-sided dolphin, harbor 
seal, northern elephant seal) that are unlikely to occur within a semi-
enclosed harbor environment were included to account for a potential 
increase in occurrence that has been previously documented for those 
species under similar climatological conditions (NAVFAC SW, 2015).

                    Table 8--Estimated Take by Level B Harassment Proposed for Authorization
----------------------------------------------------------------------------------------------------------------
                                                                                      Maximum
                                                                     Expected        estimated       Estimated
         Common name            Scientific name       Stock           average         Level B       takes as a
                                                                    individuals     harassment     percentage of
                                                                      per day          takes        population
----------------------------------------------------------------------------------------------------------------
Bottlenose dolphin \1\.......  Tursiops          California                   12              72            15.9
                                truncatus.        Coastal.
Common dolphin (long-beaked)   Delphinus         California.....             * 9            * 54              <1
 \2\.                           capensis.
Common dolphin (short-beaked)  Delphinus         California/                 * 9            * 54              <1
 \2\.                           delphis.          Oregon/
                                                  Washington.
Pacific white-sided dolphin    Lagenorhynchus    California/                   1               6              <1
 \2\.                           obliquidens.      Oregon/
                                                  Washington--No
                                                  rthern and
                                                  Southern.
California sea lion \3\......  Zalophus          U.S............             100             600              <1
                                californianus.
Harbor seal \2\..............  Phoca vitulina    California.....               3              18              <1
                                richardii.
Northern elephant seal \2\...  Mirounga          California                    1               6              <1
                                angustirostris.   breeding.
----------------------------------------------------------------------------------------------------------------
\1\ Average daily counts based on observations during Oceanside Harbor Dredging 2022 Project Monitoring, rounded
  up to nearest individual count (Merkel and Associates Inc., 2022).
\2\ Average daily counts based on observations during Year 2 of Navy Base Point Loma's Fuel Pier Replacement
  Project Monitoring, rounded up to nearest individual count (NAVFAC SW, 2015).
\3\ Reported high estimate of sea lions observed on pinniped float by Oceanside Harbor District staff.
* A total of 54 takes are estimated and may be attributed to either long- or short-beaked common dolphin
  species.

Proposed Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of the species or stock for taking for certain 
subsistence uses (latter not applicable for this action). NMFS 
regulations require applicants for incidental take authorizations to 
include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting the 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks, and their habitat (50 CFR 
216.104(a)(11)).

[[Page 83095]]

    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, NMFS 
considers two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned), the likelihood of effective implementation (probability 
implemented as planned); and
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost, and impact on 
operations.
    The City of Oceanside must ensure that construction supervisors and 
crews, the monitoring team, and relevant staff/contractors are trained 
prior to the start of all piling activities so that responsibilities, 
communication procedures, monitoring protocols, and operational 
procedures are clearly understood. New personnel joining during the 
project must be trained prior to commencing work.

Timing Restrictions

    All piling activities would be conducted during daylight hours, 
generally between 45 minutes post-sunrise and 45 minutes pre-sunset. 
All piling would occur in March 2024 and/or September 2024 through 
February 2025, when the likelihood of ESA-listed California least tern 
breeding and nesting in the work area is minimal, as proposed by the 
City of Oceanside.

Protected Species Observers

    The placement of PSOs during all pile driving activities (described 
in the Proposed Monitoring and Reporting section) would ensure that the 
entire shutdown zone is visible. Should environmental conditions 
deteriorate such that the entire shutdown zone would not be visible 
(e.g., fog, heavy rain), pile driving would be delayed until the PSO is 
confident marine mammals within the shutdown zone could be detected.
    PSOs would monitor the full shutdown zones and the Level B 
harassment zones to the extent practicable. Monitoring zones provide 
utility for observing by establishing monitoring protocols for areas 
adjacent to the shutdown zones. Monitoring zones enable observers to be 
aware of and communicate the presence of marine mammals in the project 
areas outside the shutdown zones and thus prepare for a potential 
cessation of activity should the animal enter the shutdown zone.

Pre- and Post-Activity Monitoring

    Monitoring must take place from 30 minutes prior to initiation of 
pile driving activities (i.e., pre-clearance monitoring) through 30 
minutes post-completion of pile driving. Prior to the start of daily 
in-water construction activity, or whenever a break in pile driving of 
30 minutes or longer occurs, PSOs would observe the shutdown and 
monitoring zones for a period of 30 minutes. The shutdown zone would be 
considered cleared when a marine mammal has not been observed within 
the zone for a 30-minute period. If a marine mammal is observed within 
the shutdown zones listed in table 9, pile driving activity would be 
delayed or halted. If work ceases for more than 30 minutes, the pre-
activity monitoring of the shutdown zones would commence. A 
determination that the shutdown zone is clear must be made during a 
period of good visibility (i.e., the entire shutdown zone and 
surrounding waters must be visible to the naked eye).

Soft-Start Procedures for Impact Driving

    Soft-start procedures provide additional protection to marine 
mammals by providing warning and/or giving marine mammals a chance to 
leave the area prior to the hammer operating at full capacity. If 
impact pile driving is necessary to achieve required tip elevation, 
City of Oceanside staff and/or contractors would be required to provide 
an initial set of three strikes from the hammer at reduced energy, 
followed by a 30-second waiting period, then two subsequent reduced-
energy strike sets. Soft-start would be implemented at the start of 
each day's impact pile driving and at any time following cessation of 
impact pile driving for a period of 30 minutes or longer.

Shutdown Zones

    The City of Oceanside must establish shutdown zones for all pile 
driving activities. The purpose of a shutdown zone is generally to 
define an area within which shutdown of the activity would occur upon 
sighting of a marine mammal (or in anticipation of an animal entering 
the defined area). Shutdown zones would be based upon the Level A 
harassment thresholds for each pile size/type and driving method where 
applicable, as shown in table 6. During all in-water piling activities, 
the City of Oceanside has proposed to implement a buffered 15 m 
shutdown zone, with the exception of a 180 m shutdown zone for phocids 
during the use of impact pile driving of 18-inch piles. These distances 
exceed the estimated Level A harassment isopleths described in table 6. 
Adherence to this expanded shutdown zone will avoid the potential for 
the take of phocids by Level A harassment during impact pile driving. 
For pile driving, the radii of the shutdown zones are rounded to the 
next largest 10 m interval in comparison to the Level A harassment 
isopleth for each activity type. If a marine mammal is observed 
entering, or detected within, a shutdown zone during pile driving 
activity, the activity must be stopped until there is visual 
confirmation that the animal has left the zone or the animal is not 
sighted for a period of 15 minutes. Proposed shutdown zones for each 
activity type are shown in Table 9.
    All marine mammals would be monitored in the Level B harassment 
zones and throughout the area as far as visual monitoring can take 
place. If a marine mammal enters the Level B harassment zone, in-water 
activities would continue and PSOs would document the animal's presence 
within the estimated harassment zone.

                                                     Table 9--Proposed Shutdown and Harassment Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Pile size  (inch,      Shutdown zone   Shutdown zone   Shutdown zone    Harassment
               Activity                         Method                  material)           for MF  (m)     for PW  (m)     for OW  (m)      zone  (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Extraction...........................  Vibratory...............  16, concrete...........              15              15              15           7,360
Installation.........................  Vibratory...............  18, steel..............              15              15              15           3,420
Installation.........................  Impact..................  18, steel..............              15             180              15             100
Installation.........................  Vibratory...............  10, steel..............              15              15              15           2,160
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 83096]]

    Based on our evaluation of the City of Oceanside's proposed 
measures, NMFS has preliminarily determined that the proposed 
mitigation measures provide the means of effecting the least 
practicable impact on the affected species or stocks and their habitat, 
paying particular attention to rookeries, mating grounds, and areas of 
similar significance.

Proposed Monitoring and Reporting

    In order to issue an IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104(a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present while 
conducting the activities. Effective reporting is critical both to 
compliance as well as ensuring that the most value is obtained from the 
required monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
    <bullet> Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
    <bullet> Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the activity; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
    <bullet> Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
    <bullet> How anticipated responses to stressors impact either: (1) 
long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
    <bullet> Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
    <bullet> Mitigation and monitoring effectiveness.

Visual Monitoring

    Marine mammal monitoring must be conducted in accordance with the 
conditions in this section and this IHA. Marine mammal monitoring 
during pile driving activities would be conducted by two PSOs meeting 
NMFS' standards and in a manner consistent with the following:
    <bullet> PSOs must be independent of the activity contractor (for 
example, employed by a subcontractor) and have no other assigned tasks 
during monitoring periods;
    <bullet> At least one PSO would have prior experience performing 
the duties of a PSO during construction activity pursuant to a NMFS-
issued incidental take authorization;
    <bullet> Other PSOs may substitute other relevant experience, 
education (degree in biological science or related field), or training 
for prior experience performing the duties of a PSO during construction 
activity pursuant to a NMFS-issued incidental take authorization;
    <bullet> Where a team of three or more PSOs is required, a lead 
observer or monitoring coordinator must be designated. The lead 
observer must have prior experience performing the duties of a PSO 
during construction activity pursuant to a NMFS-issued incidental take 
authorization; and
    <bullet> PSOs must be approved by NMFS prior to beginning any 
activity subject to the IHA.
    PSOs should have the following additional qualifications:
    <bullet> Ability to conduct field observations and collect data 
according to assigned protocols;
    <bullet> Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
    <bullet> Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
    <bullet> Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates, times, and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
and marine mammal behavior; and
    <bullet> Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
    The City of Oceanside would have two PSOs stationed at the best 
possible vantage points in the project area to monitor during all pile 
driving activities. Monitoring would occur from elevated locations 
along the shoreline where the entire shutdown zones are visible. PSOs 
would be equipped with high quality binoculars for monitoring and 
radios or cells phones for maintaining contact with work crews. 
Monitoring would be conducted 30 minutes before, during, and 30 minutes 
after all in-water construction activities. In addition, PSOs would 
record all incidents of marine mammal occurrence, regardless of 
distance from activity, and would document any behavioral reactions in 
concert with distance from piles being driven or removed. Pile driving 
activities include the time to install or remove a single pile or 
series of piles, as long as the time elapsed between uses of the pile 
driving equipment is no more than 30 minutes.

Reporting

    The City of Oceanside will provide the following reporting as 
necessary during active pile driving activities:
    <bullet> The applicant will report any observed injury or mortality 
as soon as feasible and in accordance with NMFS' standard reporting 
guidelines. Reports will be made by phone (866-767-6114) and by email 
(<a href="/cdn-cgi/l/email-protection#bfefed91f6ebef91f2d0d1d6cbd0cdd6d1d8eddacfd0cdcbccffd1d0dede91d8d0c9"><span class="__cf_email__" data-cfemail="5303017d1a07037d1e3c3d3a273c213a3d340136233c212720133d3c32327d343c25">[email protected]</span></a>) and will include the following:
    [cir] Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    [cir] Species identification (if known) or description of the 
animal(s) involved;
    [cir] Condition of the animal(s) (including carcass condition if 
the animal is dead);
    [cir] Observed behaviors of the animal(s), if alive;
    [cir] If available, photographs or video footage of the animal(s); 
and
    [cir] General circumstances under which the animal was discovered;
    <bullet> An annual report summarizing the prior year's activities 
will be provided that fully documents the methods and monitoring 
protocols, summarizes the data recorded during monitoring, estimates 
the number of listed marine mammals that may have been incidentally 
taken during project pile driving, and provides an interpretation of 
the results and effectiveness of all monitoring tasks. The annual draft 
report will be provided no later than 90 days following completion of 
construction activities. Any recommendations made by NMFS will be 
addressed in the final report, due

[[Page 83097]]

after the IHA expires and including a summary of all monitoring 
activities, prior to acceptance by NMFS. Final reports will follow a 
standardized format for PSO reporting from activities requiring marine 
mammal mitigation and monitoring; and
    <bullet> All PSOs will use a standardized data entry format (see 
Monitoring Plan).

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' through harassment, NMFS considers other factors, such as the 
likely nature of any impacts or responses (e.g., intensity, duration), 
the context of any impacts or responses (e.g., critical reproductive 
time or location, foraging impacts affecting energetics), as well as 
effects on habitat, and the likely effectiveness of the mitigation. We 
also assess the number, intensity, and context of estimated takes by 
evaluating this information relative to population status. Consistent 
with the 1989 preamble for NMFS' implementing regulations (54 FR 40338; 
September 29, 1989), the impacts from other past and ongoing 
anthropogenic activities are incorporated into this analysis via their 
impacts on the baseline (e.g., as reflected in the regulatory status of 
the species, population size and growth rate where known, ongoing 
sources of human-caused mortality, or ambient noise levels).
    To avoid repetition, the discussion of our analysis applies to all 
the species listed in table 2, given that the anticipated effects of 
this activity on these different marine mammal stocks are expected to 
be similar. There is little information about the nature or severity of 
the impacts, or the size, status, or structure of any of these species 
or stocks that would lead to a different analysis for this activity.
    Level A harassment is extremely unlikely given the small size of 
the Level A harassment isopleths and the required mitigation measures 
designed to minimize the possibility of injury to marine mammals (see 
Proposed Mitigation section). No mortality is anticipated given the 
nature of the activity.
    Pile installation and removal activities are likely to result in 
the Level B harassment of marine mammals that move into the ensonified 
zone, primarily in the form of disturbance or displacement of marine 
mammals.
    Take would occur within a limited, confined area of each stock's 
range. Level B harassment would be reduced to the level of least 
practicable adverse impact through use of mitigation measures described 
herein. Further, the amount of take authorized is extremely small when 
compared to stock abundance.
    No marine mammal stocks for which incidental take authorization is 
proposed are listed as threatened or endangered under the ESA or 
determined to be strategic or depleted under the MMPA. The relatively 
low marine mammal occurrences in the area, small shutdown zones, and 
proposed monitoring make injury takes of marine mammals unlikely. The 
shutdown zones would be thoroughly monitored before the proposed 
vibratory pile installation and removal begins, and construction 
activities would be postponed if a marine mammal is sighted within the 
shutdown zone. There is a high likelihood that marine mammals would be 
detected by trained observers under environmental conditions described 
for the proposed project. Limiting construction activities to daylight 
hours would also increase detectability of marine mammals in the area. 
Therefore, the proposed mitigation and monitoring measures are expected 
to eliminate the potential for injury and Level A harassment as well as 
reduce the amount and intensity for Level B behavioral harassment. 
Furthermore, the pile installation and removal activities analyzed here 
are similar to, or less impactful than, numerous construction 
activities conducted in other similar locations which have occurred 
with no reported injuries or mortality to marine mammals, and no known 
long-term adverse consequences from behavioral harassment.
    Anticipated and authorized takes are expected to be limited to 
short-term Level B harassment (behavioral disturbance) as construction 
activities will occur over the course of 5-6 months. Effects on 
individuals taken by Level B harassment, based upon reports in the 
literature as well as monitoring from other similar activities, may 
include increased swimming speeds, increased surfacing time, or 
decreased foraging (e.g., NAVFAC SW, 2018). Individual animals, even if 
taken multiple times, would likely move away from the sound source and 
be temporarily displaced from the area due to elevated noise level 
during pile removal. Marine mammals could also experience TTS if they 
move into the Level B harassment monitoring zone. TTS is a temporary 
loss of hearing sensitivity when exposed to loud sound, and, given the 
likely levels and duration of exposure to pile driving, any shift of 
the hearing threshold is expected to recover completely within minutes 
to hours. While TTS could occur, it is not considered a likely outcome 
of this activity.
    Given the limited number of total predicted exposures, no 
individual marine mammals of any species, with the possible exception 
of California sea lions, would be expected to be taken on more than a 
few days during the construction activities. California sea lions are 
relatively common in the area, and potential takes would likely involve 
sea lions loafing on, or in the vicinity of, physical structures or 
moving through the area en route to foraging areas or structures where 
they haul out. Relocation of the float where they frequently haul out 
is expected to reduce both the number of sea lions present in the area 
during construction and also the likelihood that they may be repeatedly 
impacted.
    The proposed project is not expected to have significant adverse 
effects on marine mammal habitat. There are no Biologically Important 
Areas or ESA-designated critical habitat within the project area, and 
the proposed activities would not permanently modify existing marine 
mammal habitat. The activities may cause fish to leave the area 
temporarily which could impact marine mammals' foraging opportunities 
in a limited portion of the foraging range. However, due to the short 
duration of the proposed activities and the relatively small area of 
affected habitat, the impacts to marine mammal habitat are not expected 
to cause significant or long-term negative consequences.
    In combination, we believe that these factors, as well as the 
available body of evidence from other similar activities, demonstrate 
that the potential effects of the specified activities would have only 
minor, short-term effects on individuals. The specified activities are 
not expected to impact reproduction or survival of any individual 
marine mammals, much less affect rates of recruitment or survival and 
would therefore not result in population-level impacts.
    In summary and as described above, the following factors primarily 
support our preliminary determination that the

[[Page 83098]]

impacts resulting from this activity are not expected to adversely 
affect any of the species or stocks through effects on annual rates of 
recruitment or survival:
    <bullet> No serious injury or mortality, or Level A harassment, is 
anticipated or authorized;
    <bullet> The specified activities are of a very short duration and 
associated ensonified areas are very small relative to the overall 
habitat ranges of both species;
    <bullet> The project area does not overlap with known BIAs or ESA-
designated critical habitat;
    <bullet> Significant or long-term effects to marine mammal habitat 
are not anticipated; and
    <bullet> Proposed mitigation measures are expected to reduce the 
effects of the specified activity to the level of least practicable 
adverse impact.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the proposed activity will have a negligible impact on 
all affected marine mammal species or stocks.

Small Numbers

    As noted previously, only take of small numbers of marine mammals 
may be authorized under sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness activities. The MMPA 
does not define small numbers and so, in practice, where estimated 
numbers are available, NMFS compares the number of individuals taken to 
the most appropriate estimation of abundance of the relevant species or 
stock in our determination of whether an authorization is limited to 
small numbers of marine mammals. When the predicted number of 
individuals to be taken is fewer than one-third of the species or stock 
abundance, the take is considered to be of small numbers. Additionally, 
other qualitative factors may be considered in the analysis, such as 
the temporal or spatial scale of the activities.
    The amount of take NMFS has authorized is below one-third of the 
estimated stock abundances for all seven species (see table 8). For all 
but one species, the proposed take of individuals is less than 1 
percent of the abundance of the affected stock (with the exception for 
bottlenose dolphins at less than 16 percent). This is likely a 
conservative estimate because it assumes all takes are of different 
individual animals, which is likely not the case. Some individuals may 
return multiple times in a day, but PSOs would count them as separate 
takes if they cannot be individually identified.
    Based on the analysis contained herein of the proposed activity 
(including the proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS preliminarily finds that small 
numbers of marine mammals would be taken relative to the population 
size of the affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. Therefore, NMFS has 
determined that the total taking of affected species or stocks would 
not have an unmitigable adverse impact on the availability of such 
species or stocks for taking for subsistence purposes.

Endangered Species Act

    Section 7(a)(2) of the ESA of 1973 (16 U.S.C. 1531 et seq.) 
requires that each Federal agency insure that any action it authorizes, 
funds, or carries out is not likely to jeopardize the continued 
existence of any endangered or threatened species or result in the 
destruction or adverse modification of designated critical habitat. To 
ensure ESA compliance for the issuance of IHAs, NMFS consults 
internally whenever we propose to authorize take for endangered or 
threatened species.
    No incidental take of ESA-listed species is proposed for 
authorization or expected to result from this activity. Therefore, NMFS 
has determined that formal consultation under section 7 of the ESA is 
not required for this action.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to the City of Oceanside for conducting pile removal and 
driving in Oceanside Harbor, Oceanside, CA, provided the previously 
mentioned mitigation, monitoring, and reporting requirements are 
incorporated. A draft of the proposed IHA can be found at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities.

Request for Public Comments

    We request comment on our analyses, the proposed authorization, and 
any other aspect of this notice of proposed IHA for the proposed 
construction project. We also request comment on the potential renewal 
of this proposed IHA as described in the paragraph below. Please 
include with your comments any supporting data or literature citations 
to help inform decisions on the request for this IHA or a subsequent 
renewal IHA.
    On a case-by-case basis, NMFS may issue a one-time, one-year 
renewal IHA following notice to the public providing an additional 15 
days for public comments when (1) up to another year of identical or 
nearly identical activities as described in the Description of Proposed 
Activity section of this notice is planned or (2) the activities as 
described in the Description of Proposed Activity section of this 
notice would not be completed by the time the IHA expires and a renewal 
would allow for completion of the activities beyond that described in 
the Dates and Duration section of this notice, provided all of the 
following conditions are met:
    <bullet> A request for renewal is received no later than 60 days 
prior to the needed renewal IHA effective date (recognizing that the 
renewal IHA expiration date cannot extend beyond one year from 
expiration of the initial IHA); and
    <bullet> The request for renewal must include the following:
    (1) An explanation that the activities to be conducted under the 
requested renewal IHA are identical to the activities analyzed under 
the initial IHA, are a subset of the activities, or include changes so 
minor (e.g., reduction in pile size) that the changes do not affect the 
previous analyses, mitigation and monitoring requirements, or take 
estimates (with the exception of reducing the type or amount of take); 
and
    (2) A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized.
    Upon review of the request for renewal, the status of the affected 
species or stocks, and any other pertinent information, NMFS determines 
that there are no more than minor changes in the activities, the 
mitigation and monitoring measures will remain the same and 
appropriate, and the findings in the initial IHA remain valid.

    Dated: November 20, 2023.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2023-26158 Filed 11-27-23; 8:45 am]
BILLING CODE 3510-22-P


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